﻿#region License
// Copyright (c) 2007 James Newton-King
//
// Permission is hereby granted, free of charge, to any person
// obtaining a copy of this software and associated documentation
// files (the "Software"), to deal in the Software without
// restriction, including without limitation the rights to use,
// copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following
// conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
// OTHER DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Collections.Generic;
using System.Reflection;
#if NET20
using Newtonsoft.Json.Utilities.LinqBridge;
#else
using System.Linq;
#endif

namespace Newtonsoft.Json.Utilities
{
    internal static class TypeExtensions
    {
#if NETFX_CORE || PORTABLE
        private static BindingFlags DefaultFlags = BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance;

        public static MethodInfo GetGetMethod(this PropertyInfo propertyInfo)
        {
            return propertyInfo.GetGetMethod(false);
        }

        public static MethodInfo GetGetMethod(this PropertyInfo propertyInfo, bool nonPublic)
        {
            MethodInfo getMethod = propertyInfo.GetMethod;
            if (getMethod != null && (getMethod.IsPublic || nonPublic))
                return getMethod;

            return null;
        }

        public static MethodInfo GetSetMethod(this PropertyInfo propertyInfo)
        {
            return propertyInfo.GetSetMethod(false);
        }

        public static MethodInfo GetSetMethod(this PropertyInfo propertyInfo, bool nonPublic)
        {
            MethodInfo setMethod = propertyInfo.SetMethod;
            if (setMethod != null && (setMethod.IsPublic || nonPublic))
                return setMethod;

            return null;
        }

        public static bool IsSubclassOf(this Type type, Type c)
        {
            return type.GetTypeInfo().IsSubclassOf(c);
        }

        public static bool IsAssignableFrom(this Type type, Type c)
        {
            return type.GetTypeInfo().IsAssignableFrom(c.GetTypeInfo());
        }
#endif

        public static MethodInfo Method(this Delegate d)
        {
#if !(NETFX_CORE || PORTABLE)
            return d.Method;
#else
            return d.GetMethodInfo();
#endif
        }

        public static MemberTypes MemberType(this MemberInfo memberInfo)
        {
#if !(NETFX_CORE || PORTABLE || PORTABLE40)
            return memberInfo.MemberType;
#else
            if (memberInfo is PropertyInfo)
                return MemberTypes.Property;
            else if (memberInfo is FieldInfo)
                return MemberTypes.Field;
            else if (memberInfo is EventInfo)
                return MemberTypes.Event;
            else if (memberInfo is MethodInfo)
                return MemberTypes.Method;
            else
                return MemberTypes.Other;
#endif
        }

        public static bool ContainsGenericParameters(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.ContainsGenericParameters;
#else
            return type.GetTypeInfo().ContainsGenericParameters;
#endif
        }

        public static bool IsInterface(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsInterface;
#else
            return type.GetTypeInfo().IsInterface;
#endif
        }

        public static bool IsGenericType(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsGenericType;
#else
            return type.GetTypeInfo().IsGenericType;
#endif
        }

        public static bool IsGenericTypeDefinition(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsGenericTypeDefinition;
#else
            return type.GetTypeInfo().IsGenericTypeDefinition;
#endif
        }

        public static Type BaseType(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.BaseType;
#else
            return type.GetTypeInfo().BaseType;
#endif
        }

        public static Assembly Assembly(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.Assembly;
#else
            return type.GetTypeInfo().Assembly;
#endif
        }

        public static bool IsEnum(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsEnum;
#else
            return type.GetTypeInfo().IsEnum;
#endif
        }

        public static bool IsClass(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsClass;
#else
            return type.GetTypeInfo().IsClass;
#endif
        }

        public static bool IsSealed(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsSealed;
#else
            return type.GetTypeInfo().IsSealed;
#endif
        }

#if PORTABLE40
        public static PropertyInfo GetProperty(this Type type, string name, BindingFlags bindingFlags, object placeholder1, Type propertyType, IList<Type> indexParameters, object placeholder2)
        {
            IList<PropertyInfo> propertyInfos = type.GetProperties(bindingFlags);

            return propertyInfos.Where(p =>
            {
                if (name != null && name != p.Name)
                    return false;
                if (propertyType != null && propertyType != p.PropertyType)
                    return false;
                if (indexParameters != null)
                {
                    if (!p.GetIndexParameters().Select(ip => ip.ParameterType).SequenceEqual(indexParameters))
                        return false;
                }

                return true;
            }).SingleOrDefault();
        }

        public static IEnumerable<MemberInfo> GetMember(this Type type, string name, MemberTypes memberType, BindingFlags bindingFlags)
        {
            return type.GetMembers(bindingFlags).Where(m =>
            {
                if (name != null && name != m.Name)
                    return false;
                if (m.MemberType() != memberType)
                    return false;

                return true;
            });
        }
#endif

#if (NETFX_CORE || PORTABLE)
        public static MethodInfo GetBaseDefinition(this MethodInfo method)
        {
            return method.GetRuntimeBaseDefinition();
        }
#endif

#if (NETFX_CORE || PORTABLE)
        public static bool IsDefined(this Type type, Type attributeType, bool inherit)
        {
            return type.GetTypeInfo().CustomAttributes.Any(a => a.AttributeType == attributeType);
        }

        public static MethodInfo GetMethod(this Type type, string name)
        {
            return type.GetMethod(name, DefaultFlags);
        }

        public static MethodInfo GetMethod(this Type type, string name, BindingFlags bindingFlags)
        {
            return type.GetTypeInfo().GetDeclaredMethod(name);
        }

        public static MethodInfo GetMethod(this Type type, IList<Type> parameterTypes)
        {
            return type.GetMethod(null, parameterTypes);
        }

        public static MethodInfo GetMethod(this Type type, string name, IList<Type> parameterTypes)
        {
            return type.GetMethod(name, DefaultFlags, null, parameterTypes, null);
        }

        public static MethodInfo GetMethod(this Type type, string name, BindingFlags bindingFlags, object placeHolder1, IList<Type> parameterTypes, object placeHolder2)
        {
            return type.GetTypeInfo().DeclaredMethods.Where(m =>
                                                                {
                                                                    if (name != null && m.Name != name)
                                                                        return false;

                                                                    if (!TestAccessibility(m, bindingFlags))
                                                                        return false;

                                                                    return m.GetParameters().Select(p => p.ParameterType).SequenceEqual(parameterTypes);
                                                                }).SingleOrDefault();
        }

        public static PropertyInfo GetProperty(this Type type, string name, BindingFlags bindingFlags, object placeholder1, Type propertyType, IList<Type> indexParameters, object placeholder2)
        {
            return type.GetTypeInfo().DeclaredProperties.Where(p =>
                                                                   {
                                                                       if (name != null && name != p.Name)
                                                                           return false;
                                                                       if (propertyType != null && propertyType != p.PropertyType)
                                                                           return false;
                                                                       if (indexParameters != null)
                                                                       {
                                                                           if (!p.GetIndexParameters().Select(ip => ip.ParameterType).SequenceEqual(indexParameters))
                                                                               return false;
                                                                       }

                                                                       return true;
                                                                   }).SingleOrDefault();
        }

        public static IEnumerable<MemberInfo> GetMember(this Type type, string name, MemberTypes memberType, BindingFlags bindingFlags)
        {
            return type.GetTypeInfo().GetMembersRecursive().Where(m =>
                                                                      {
                                                                          if (name != null && name != m.Name)
                                                                              return false;
                                                                          if (m.MemberType() != memberType)
                                                                              return false;
                                                                          if (!TestAccessibility(m, bindingFlags))
                                                                              return false;

                                                                          return true;
                                                                      });
        }

        public static IEnumerable<ConstructorInfo> GetConstructors(this Type type)
        {
            return type.GetConstructors(DefaultFlags);
        }

        public static IEnumerable<ConstructorInfo> GetConstructors(this Type type, BindingFlags bindingFlags)
        {
            return type.GetConstructors(bindingFlags, null);
        }

        private static IEnumerable<ConstructorInfo> GetConstructors(this Type type, BindingFlags bindingFlags, IList<Type> parameterTypes)
        {
            return type.GetTypeInfo().DeclaredConstructors.Where(c =>
                                                                     {
                                                                         if (!TestAccessibility(c, bindingFlags))
                                                                             return false;

                                                                         if (parameterTypes != null && !c.GetParameters().Select(p => p.ParameterType).SequenceEqual(parameterTypes))
                                                                             return false;

                                                                         return true;
                                                                     });
        }

        public static ConstructorInfo GetConstructor(this Type type, IList<Type> parameterTypes)
        {
            return type.GetConstructor(DefaultFlags, null, parameterTypes, null);
        }

        public static ConstructorInfo GetConstructor(this Type type, BindingFlags bindingFlags, object placeholder1, IList<Type> parameterTypes, object placeholder2)
        {
            return type.GetConstructors(bindingFlags, parameterTypes).SingleOrDefault();
        }

        public static MemberInfo[] GetMember(this Type type, string member)
        {
            return type.GetMember(member, DefaultFlags);
        }

        public static MemberInfo[] GetMember(this Type type, string member, BindingFlags bindingFlags)
        {
            return type.GetTypeInfo().GetMembersRecursive().Where(m => m.Name == member && TestAccessibility(m, bindingFlags)).ToArray();
        }

        public static MemberInfo GetField(this Type type, string member)
        {
            return type.GetField(member, DefaultFlags);
        }

        public static MemberInfo GetField(this Type type, string member, BindingFlags bindingFlags)
        {
            return type.GetTypeInfo().GetDeclaredField(member);
        }

        public static IEnumerable<PropertyInfo> GetProperties(this Type type, BindingFlags bindingFlags)
        {
            IList<PropertyInfo> properties = (bindingFlags.HasFlag(BindingFlags.DeclaredOnly))
                                                 ? type.GetTypeInfo().DeclaredProperties.ToList()
                                                 : type.GetTypeInfo().GetPropertiesRecursive();

            return properties.Where(p => TestAccessibility(p, bindingFlags));
        }

        private static IList<MemberInfo> GetMembersRecursive(this TypeInfo type)
        {
            TypeInfo t = type;
            IList<MemberInfo> members = new List<MemberInfo>();
            while (t != null)
            {
                foreach (var member in t.DeclaredMembers)
                {
                    if (!members.Any(p => p.Name == member.Name))
                        members.Add(member);
                }
                t = (t.BaseType != null) ? t.BaseType.GetTypeInfo() : null;
            }

            return members;
        }

        private static IList<PropertyInfo> GetPropertiesRecursive(this TypeInfo type)
        {
            TypeInfo t = type;
            IList<PropertyInfo> properties = new List<PropertyInfo>();
            while (t != null)
            {
                foreach (var member in t.DeclaredProperties)
                {
                    if (!properties.Any(p => p.Name == member.Name))
                        properties.Add(member);
                }
                t = (t.BaseType != null) ? t.BaseType.GetTypeInfo() : null;
            }

            return properties;
        }

        private static IList<FieldInfo> GetFieldsRecursive(this TypeInfo type)
        {
            TypeInfo t = type;
            IList<FieldInfo> fields = new List<FieldInfo>();
            while (t != null)
            {
                foreach (var member in t.DeclaredFields)
                {
                    if (!fields.Any(p => p.Name == member.Name))
                        fields.Add(member);
                }
                t = (t.BaseType != null) ? t.BaseType.GetTypeInfo() : null;
            }

            return fields;
        }

        public static IEnumerable<MethodInfo> GetMethods(this Type type, BindingFlags bindingFlags)
        {
            return type.GetTypeInfo().DeclaredMethods;
        }

        public static PropertyInfo GetProperty(this Type type, string name)
        {
            return type.GetProperty(name, DefaultFlags);
        }

        public static PropertyInfo GetProperty(this Type type, string name, BindingFlags bindingFlags)
        {
            return type.GetTypeInfo().GetDeclaredProperty(name);
        }

        public static IEnumerable<FieldInfo> GetFields(this Type type)
        {
            return type.GetFields(DefaultFlags);
        }

        public static IEnumerable<FieldInfo> GetFields(this Type type, BindingFlags bindingFlags)
        {
            IList<FieldInfo> fields = (bindingFlags.HasFlag(BindingFlags.DeclaredOnly))
                                          ? type.GetTypeInfo().DeclaredFields.ToList()
                                          : type.GetTypeInfo().GetFieldsRecursive();

            return fields.Where(f => TestAccessibility(f, bindingFlags)).ToList();
        }

        private static bool TestAccessibility(PropertyInfo member, BindingFlags bindingFlags)
        {
            if (member.GetMethod != null && TestAccessibility(member.GetMethod, bindingFlags))
                return true;

            if (member.SetMethod != null && TestAccessibility(member.SetMethod, bindingFlags))
                return true;

            return false;
        }

        private static bool TestAccessibility(MemberInfo member, BindingFlags bindingFlags)
        {
            if (member is FieldInfo)
            {
                return TestAccessibility((FieldInfo) member, bindingFlags);
            }
            else if (member is MethodBase)
            {
                return TestAccessibility((MethodBase) member, bindingFlags);
            }
            else if (member is PropertyInfo)
            {
                return TestAccessibility((PropertyInfo) member, bindingFlags);
            }

            throw new Exception("Unexpected member type.");
        }

        private static bool TestAccessibility(FieldInfo member, BindingFlags bindingFlags)
        {
            bool visibility = (member.IsPublic && bindingFlags.HasFlag(BindingFlags.Public)) ||
                              (!member.IsPublic && bindingFlags.HasFlag(BindingFlags.NonPublic));

            bool instance = (member.IsStatic && bindingFlags.HasFlag(BindingFlags.Static)) ||
                            (!member.IsStatic && bindingFlags.HasFlag(BindingFlags.Instance));

            return visibility && instance;
        }

        private static bool TestAccessibility(MethodBase member, BindingFlags bindingFlags)
        {
            bool visibility = (member.IsPublic && bindingFlags.HasFlag(BindingFlags.Public)) ||
                              (!member.IsPublic && bindingFlags.HasFlag(BindingFlags.NonPublic));

            bool instance = (member.IsStatic && bindingFlags.HasFlag(BindingFlags.Static)) ||
                            (!member.IsStatic && bindingFlags.HasFlag(BindingFlags.Instance));

            return visibility && instance;
        }

        public static Type[] GetGenericArguments(this Type type)
        {
            return type.GetTypeInfo().GenericTypeArguments;
        }

        public static IEnumerable<Type> GetInterfaces(this Type type)
        {
            return type.GetTypeInfo().ImplementedInterfaces;
        }

        public static IEnumerable<MethodInfo> GetMethods(this Type type)
        {
            return type.GetTypeInfo().DeclaredMethods;
        }
#endif

        public static bool IsAbstract(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsAbstract;
#else
            return type.GetTypeInfo().IsAbstract;
#endif
        }

        public static bool IsVisible(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsVisible;
#else
            return type.GetTypeInfo().IsVisible;
#endif
        }

        public static bool IsValueType(this Type type)
        {
#if !(NETFX_CORE || PORTABLE)
            return type.IsValueType;
#else
            return type.GetTypeInfo().IsValueType;
#endif
        }

        public static bool AssignableToTypeName(this Type type, string fullTypeName, out Type match)
        {
            Type current = type;

            while (current != null)
            {
                if (string.Equals(current.FullName, fullTypeName, StringComparison.Ordinal))
                {
                    match = current;
                    return true;
                }

                current = current.BaseType();
            }

            foreach (Type i in type.GetInterfaces())
            {
                if (string.Equals(i.Name, fullTypeName, StringComparison.Ordinal))
                {
                    match = type;
                    return true;
                }
            }

            match = null;
            return false;
        }

        public static bool AssignableToTypeName(this Type type, string fullTypeName)
        {
            Type match;
            return type.AssignableToTypeName(fullTypeName, out match);
        }

        public static MethodInfo GetGenericMethod(this Type type, string name, params Type[] parameterTypes)
        {
            var methods = type.GetMethods().Where(method => method.Name == name);

            foreach (var method in methods)
            {
                if (method.HasParameters(parameterTypes))
                    return method;
            }

            return null;
        }

        public static bool HasParameters(this MethodInfo method, params Type[] parameterTypes)
        {
            var methodParameters = method.GetParameters().Select(parameter => parameter.ParameterType).ToArray();

            if (methodParameters.Length != parameterTypes.Length)
                return false;

            for (int i = 0; i < methodParameters.Length; i++)
                if (methodParameters[i].ToString() != parameterTypes[i].ToString())
                    return false;

            return true;
        }

        public static IEnumerable<Type> GetAllInterfaces(this Type target)
        {
            foreach (var i in target.GetInterfaces())
            {
                yield return i;
                foreach (var ci in i.GetInterfaces())
                {
                    yield return ci;
                }
            }
        }

        public static IEnumerable<MethodInfo> GetAllMethods(this Type target)
        {
            var allTypes = target.GetAllInterfaces().ToList();
            allTypes.Add(target);

            return from type in allTypes
                   from method in type.GetMethods()
                   select method;
        }
    }
}